Roux-en-Y Gastric Bypass (RYGB) Versus Omega-Loop Gastric Bypass (OLGB) Safety and Efficacy Short-term Study (ROSESS)

Roux-en-Y Gastric Bypass (RYGB) Versus Omega-Loop Gastric Bypass (OLGB) Safety and Efficacy Short-term Study

Prospective Randomized Controlled Clinical Study Comparing Two Bariatric Bypass Procedures, Roux-en-Y Gastric Bypass (RYGB) and Omega-Loop Gastric Bypass (OLGB), in Patients With Severe Obesity and Metabolic Disease

The aim of this study is to compare the relative clinical outcomes between two variants of gastric bypass [Roux-en-Y Gastric Bypass (RYGB) or Omega-Loop Gastric Bypass (OLGB)] in metabolic surgery candidates with Body Mass Index (BMI) between 35 and 50. The study will examine the short and medium term effects of each intervention on weight, obesity comorbidities, quality of life and gastroscopy findings.

Introduction: Obesity is a risk factor for Diabetes, Ischemic heart disease, Stroke, and Hypertensive heart disease, which are the 6th, 1st, 2nd, and 10th leading causes of death according to the WHO. Bariatric or Metabolic Surgery is an Efficient and reasonably Safe method for the Treatment of Severe Obesity, Type 2 Diabetes (T2DM) and Metabolic Syndrome (MS). Existing knowledge: Metabolic procedures, e.g. Gastric bypass, are more effective in the treatment of T2DM than predominantly "restrictive" procedures, e.g. Gastric Banding. RYGB is one of the most prevalent procedures in the world and Europe. In the USA, RYGB is considered a "golden standard" in bariatric surgery. In the recent decade, a simpler variant of Gastric bypass, i.e. OLGB, has been proposed. Proponents of OLGB argue it has less complications and seems to have higher and more durable effect on weight reduction and T2DM improvement. Opponents of OLGB are concerned that chronic exposure of gastric or esophageal mucosa to bile, as seen in animal experiments and in patients operated for gastric cancer or peptic ulcer disease, pose a severe health risk. So far, this concerns has not been confirmed in OLGB patients. Only one Randomized Controlled Trial (RCT) of these two interventions was performed, concluding OLGB to be simpler and safer with a similar Efficacy 2 years after the surgery. Need for a trial: A growing evidence supports the efficacy and safety of bariatric and metabolic surgery for the treatment of severe obesity and T2DM. Therefore, bariatric surgery is being more frequently performed. However, there is little evidence from randomized trials comparing different bariatric procedures - most comes from retrospective cohorts, which might suffer from bias. As a result, the choice of a bariatric procedure for a particular patient is based largely on the preference and experience of the particular surgeon, rather than evidence of best benefit for a particular patient. Although the efficacy and safety of RYGB is well established, newer variants or other less frequently employed bariatric procedures might offer more preferable Efficacy or Safety profile for some patients. Some evidence suggests OLGB might a promising procedure, which is "simpler and safer with similar efficacy" in comparison to RYGB, a technically more demanding procedure. This study contributes with rigorous evidence to further define the relative strengths and weaknesses of OLGB as compared to the "gold standard" RYGB. Objectives: The purpose of this study is to objectively compare the efficacy of RYGB and OLGB on weight, T2DM and other obesity-related comorbidities. Furthermore, this study aims to provide more insight into the safety of OLGB and RYGB by measuring the incidence of complications and abnormal findings on Gastroscopy.

Laparoscopic Gastric Bypass performed with two anastomoses (gastro-enteral and entero- enteral), two limbs (Alimentary limb of length 150cm and Biliary limb of length 75-100cm) and sewing of mesenteric defect.

Laparoscopic Gastric Bypass performed with single anastomosis (gastro-enteral) connecting a long gastric pouch to small bowel with Afferent limb of length 200cm.

Composite measure of success of bariatric surgery as measured by Bariatric Analysis and Reporting Outcome System (BAROS)

Change in Type 2 Diabetes Mellitus, measured as intensity of medical treatment: increased, same, decreased, or discontinued

Change in Type 2 Diabetes Mellitus, measured as intensity of treatment: diet alone, oral antidiabetic agent(s), insulin (IU/day)

Durability of change in Type 2 Diabetes Mellitus, measured as proportion of patients with T2DM partial remission who experience T2DM "relapse"

Change in Hypertension, measured as intensity of medical treatment: increased, same, decreased, or discontinued

Change in Dyslipidemia, measured as intensity of medical treatment: increased, same, decreased, or discontinued

Incidence of Ulcer or other Abnormal Finding on Endoscopic Gastroscopy, measured as proportion of patients with abnormal finding in each arm

Incidence of Ulcer or other Abnormal Finding on Endoscopic Gastroscopy, measured as Rate of unique Event per 100 patient-years of follow up

Incidence of early postoperative (<=30 days) Reoperations and Complications of grade >= 2 according to Clavien-Dindo classification

Incidence of Reoperations, Complications, and detected adverse outcomes, measured as Rate of Event per 100 patient-years of follow up

Change in body weight, measured as proportion of patients with EWL > 50%, and proportion of patients with EWL < 25%

Inclusion Criteria: Severe Obesity: BMI ≥ 40 and ≤ 50 or (BMI ≥ 35 and < 40 and type 2 diabetes or metabolic syndrome) Inadequate results of Attempts to loose weight by Conservative means Ability to understand the nature of the procedure and willing to follow postoperative routine lifestyle and checkups no contraindication for bariatric surgery on psychological assessment no contraindication for general anesthesia consent for both variants of gastric bypass surgery consent to participate in a study with randomized design Exclusion Criteria: prior bariatric surgery of any kind gravidity or recent (<1 year) labour drug or alcohol abuse symptomatic Gastro Esophageal Reflux Disease (GERD) hiatal hernia, > 3cm esophagitis, ≥ 2. grade active smoker chronic renal disease, stage ≥ 3 patient immobility surgery not covered by universal insurance in Czech rep. (i.e. international patients)

Laparoscopic Roux-en-Y versus mini-gastric bypass for the treatment of morbid obesity: a prospective randomized controlled clinical trial.

Laparoscopic Roux-en-Y Vs. Mini-gastric Bypass for the Treatment of Morbid Obesity: a 10-Year Experience

Greater Weight Loss with the Omega Loop Bypass Compared to the Roux-en-Y Gastric Bypass: a Comparative Study